Telephone switching system.



H. P. CLAUSEN.

TELEPHONE SWlTCHING SYSTEM.

I APPLICATION FILED SEPT.2. 1916.

1 ,2 1 4,5 l 2 Patented Feb. 6, 1917.

//7 en-for. Henry 1? Clause/7.

by M

HENRY P. CLAUSEN, 0F MOUNT COMPANY, INCORPORATED, OF NE'W ZOE VERNON, NEW YORK, ASSIGNOR TO WESTERN ELECTRIC N. Y., A COROEATION OF NEVT YORK.

TELEPHONE SWITCHING SYSTEM.

Specification of Letters Patent.

Patented Feb. 6, 1917..

Application filed September 2, 1916. Serial No. 118,242.

To all whom it may concern.

Be it known that I, HENRY P. CLAUsEN, a citizen of the United States, residing at Mount Vernon, in the county of \Vestchester and State of New York, have invented certain new and useful Improvements in Telephone Switching Systems, of which the following is a full, clear, concise, and exact description.

This invention relates to telephone switching systems of the manual type, and has for its object the provision of means for facilitating the handling of calls during extremely busy hours with only the regular number of operators, whereby no subscriber is compelled to wait an unusual period of time for attention.

In accordance with the general features of this invention, means are provided. for automatically distributing unanswered calls from one operators position to another in case such calls have been left unanswered for a predetermined period of time. To accomplish this there is provided for each line circuit a time-controlled relay, the operation of which starts an automatic switch, which automatically picks up the waiting line and extends it to a position in front of another regular operator. Preferably only the positions which have the largest number of calls during a busy period are provided with the time-controlled relays in the line circuits, and the calls are transferred by the automatic switching means to positions at which terminate the less busy lines. Two or three automatic switches for each hundred lines of a busy position are sufficient to handle efliciently the small percentage of calls in a well managed exchange which might be left unanswered for ten seconds or more during a surge in business.

This invention will be better understood from a consideration of the following detailed description, taken in connection with the drawing in which is shown so much of a system of this kind as is necessary to illustrate the invention.

Before proceeding with a description of the operation of the illustrated system, portions of the apparatus will be described briefly. A line circuit 5, connected to a subseribers station terminating in a line jack A at an operators position, has associated therewith a time-controlled or slow-operating relay 6, adapted, when energized, to close its alternate contact at the expiration of a aredetermined period. A group relay 7, common to a group of say ten line circuits, serves to start a finder switch 8 in operation. A vertical magnet 9 and a rotary magnet 10 control the iiinler switch. Associated with the finder switch 8 is a side switch, comprising wipers 15, 16, 17, 18, 19, the movement of which is controlled by a slow-releasing side-sr-xitch magnet 20. A. release magnet 21 is employed for restoring the finder switch and associated side switch to normal position. For furnishing current impulses for operating the vertical and rotary magnets 9 and 10 there is provided an interrupter relay 22. The finder switch, associated side switch and controlling apparatus just referred to is of the type shown in Fig. 3 of and described in Patent No. 1,1a7,390 to C. L. Goodrum. This finder switch is adapted, when operated, to extend the line circuit 5 to a jack B located at another operators position.

The operation of the system is as follows: Upon the removal of the receiver from its switchhook by the subscriber at the station connected with the line circuit 5, line relay 25 operates, causing the lighting of line lamp 26 and the energization of the timecontrolled relay 6. If the operator at the position in which the line lamp 26 is located is not busy, the call will be taken up by the operator thereat by the insertion of the plug of the cord circuit G into the jack A. Cut-oil relay 9.7 will thereupon be operated, opening the circuit of line relay 25, causing the eii'acement of line lamp 2G and the dei nergization of the time-controlled relay 6. However, should this operator have been busy, or not have responded to the lighted condition of line lamp 26 within the predetermined period required for the operation of the timecontrolled relay 6, this relay will open its normal and close its alternate contacts. Group relay 7 is thereby actuated to per form two functions,one to cause the op eration of the side-switch magnet 20 over a circuit from battery through the winding of side-switch magnet 20, normal contact 28, on the finder switch 8, side-switch wiper 19 and contact 9.9 of group relay 7 to ground, and the other-to cause the intermittent operation of interrupter relay 22 over a circuit from battery through contact 80 of interrupter relay 22, and contact 35 of group relay 7 to ground. The operation of the side-switch magnet 20 completes a holding circuit therefor from battery through winding and contact 36 of side-switch magnet 20, side-switch wiper 18, test brush 37 and the lower and normal contact of test strip 38 to ground. The operation of side-switch magnet 20 also closes its contact 39, whereupon, when interrupter relay 22 is energized, the vertical magnet 9 is, energized over a circuit from battery through altercontact of interrupter relay 22, contact 39 of side-switch magnet 20, winding of vertical magnet 9 and side-switch arm 17 to ground, to raise the finder switch shaft with its test brush 37 and other brushes i0, ii, 4.2, and to the first level, and to open contact 28. At the first level, the test brush 27 finds the first level contact of test strip 38 grounded, so the side-switch magnet 20 remains energized. Current impulses through the vertical magnet 9 from battery, controlled by the interrupter relay 22, cause the vertical movement of the finder switch from level to level, until the level is. found in which there is no ground on the corresponding contact of the test strip 38. In the pres-' ent case, there is no ground on the contact of the test strip 38 corresponding to the third level, because group relay 7 is operated. Hence, when the finder switch has moved to the third level, side-switch magnet 20 is dee'nergized, moving the sideswitch wipers 15 to 19 inclusive into the second position. Rotary magnet 10 is then energized over a circuit from battery through alternate contact of interrupter relay 22, winding of the rotary magnet 10 and sideswitch wiper 17 to ground. The energization of the rotary magnet 10 causes the finder switch to rotate one step and the closure of contact 50; whereupon side-switch magnet 20 is energized over a circuit from battery through winding of side-switch magnet 20, contact 50 of rotary magnet 10, sideswitch wiper 18, brush 43 and normal contact of a deencrgizcd time-controlled relay of another line of the group of which line 5 is a part. Upon the energization of sideswitch magnet 20, a holding circuit therefor, by way of contact 36, is established. In response to each current impulse through the rotary magnet 10, the finder switch will move one step until the finder brush 43 engages a non-grounded terminal, (in the 7 present case the terminal associated with line circuit 5) whereupon side-switch magnet 20 is deenergized, moving the side-switch wipers 15 to 19 inclusive into the third position. The cut-ofi relay 27 is thereupon energized over a circuit from battery through winding of cut-ofl relay 27, finder brush 42 and side-switch wiper 17 to ground, whereupon line relay 25, timercontrolled relay 6 Line relay 51, associated with jack B, now

operates, causing the lighting of line lamp The operator at the position in which line lamp 52 18 located, now takes up the call by inserting the plug of a cord circuit.

(similar to G) into jack B, causing the operation of cut-oil" relay line relay 51 and efi'acing the line lamp 52. The operation of the cut-offrelay 53. also causes the operation of a slow'release relay 53, thereby releasing 5%, which, at the conclusion of the conversation, when the plug is withdrawn from the jack B and the cutoff relay 53 releases, cooperates with the normal contact of the cut-01f relay to momentarily complete an energizing circuit for the release magnet 21. The release magnet 21 thereupon. operates to restore the finder switch and associated side switch to normal position. and release the cut-off relay 27.

What is claimed is:

1. In a telephone exchange system, an operators switching position, telephone lines terminating thereat, line signals for each of said lines, a time-controlled switching device for each ofsaid' lines operating in conjunction with the line signal, a second'operators position, and automatic switching means common to a plurality of lines on said first mentioned position and controlled by said time-controlled mechanism to extend a line with an unanswered call to said second mentioned opcrators position. 7

2. In a telephone exchange system, an operators switching position, telephone lines terminating thereat, line signaling mechanism for each of said lines, a time-controlled switching mechanism for each line adapted-to be operated by the operation of said line signaling mechanism, a second operators position, and automaticswitching means common to a group of lines terminatingon said first mentioned operator-"s position andzoperated in response to the operation of thetimecontrolled switching mechanism associated with any one of the lines of the particular group to extend said line to said second mentioned operators position for service.

3. In a telephone exchangesystem, an op-.'

1,21e,ois

operation of the line signaling mechanism to cause the operation of the automatic switching mechanism.

4. In a telephone exchange system, an operators switching position, telephone lines terminating thereat, a line relay for each line, a second operators position, automatic switching mechanism common to the lines for extending any one thereof to the second operators position, and a slow-operating relay for each line actuated at the expiration of a predetermined period after the operation of the line relay to cause the operation of the automatic switching mechanism.

5. In a telephone exchange system, an operators switching position, telephone lines terminating thereat, a line relay for each line, a second operators position, automatic switching mechanism common to the lines for extending any one thereof to the second operators position, a slow-operating relay for each line actuated at the expiration of a predetermined period after the operation of the line relay to cause the operation of the automatic switching mechanism, and a signaling device at the second operators position operated upon the extension thereto of one of the telephone lines.

6. In a telephone exchange system, an operators switching position, telephone lines terminating thereat, line signaling mechanism for each of said lines, a time-controlled switching mechanism for each line adapted to be operated by the operation of said line signaling mechanism, a second operators position, automatic switching means common to a group of lines terminating on said first mentioned operators position and operated in response to the operation of the timecontrolled switching mechanism associated with any one of the lines of the particular group to extend said line to said second mentioned operators position for service, and a signaling device at the second operators position operated upon the extension thereto of one of the telephone lines.

In witness whereof, I hereunto subscribe my name this 1st day of September A. 1).,

HENRY P. CLAUSEN.

fiopies of this patent may be obtained for five cents each, by addressing the "Commissioner of Patents, Washington, D. 0. 

